1. Field of the Invention
The present invention relates to a developer composition. The present invention also relates to a developer.
2. Description of the Related Prior Art
Fabrication of the integrated circuits, print circuit boards, and liquid crystal displays with subtle pattern often involved coating a photoresist or a radiation sensitive resin composition on an article to be processed, and then patterning the coating film by radiation. Thereafter with an alkaline developer the article is developed to remove unwanted coatings for superb patterns.
Typical used methods for developing including immersion development, shaking development, spraying development and puddle development. Generally the photoresist is prepared by using together alkali-soluble resins such as novolac, acrylic polymers, and poly para-hydroxy styrene with different radiation sensitive matters to obtain a positive or a negative photoresist, and by radiating, the solubility is altered and allows the photoresist to be dissolved in the alkaline developer. Alkaline materials such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, tetra-methyl ammonium hydroxide or alkanolamine are widely used in developers.
According to the conventional developing technology, after the photoresist is coated, heated and exposed, an alkaline developer is dissolved with to remove the unwanted unexposed coated region of film, photoresist having acidic functional groups are responsible for the developed shadows. The acid group of the organic polymer will be neutralized in an alkaline solution to form a water soluble organic polymeric salt. When the dissolving photoresist accumulates in the solution, insoluble organic materials are formed in the developing tank, and water insoluble residues and scum are obtained in the end. Developing along with these sediments, undeveloped partial particles or insoluble residues has a higher tendency to form and resulting in imprecise photoresist pattern. To improve the flaws of the aforementioned, surfactants are added to reduce the likelihood for scum formations. As the Japanese Patent application Laid-open No. 7-120935 and Laid-open No. 9-34128 already disclosed, where phenol or nonylphenol of the ethylene oxide nonionic surfactants have the capability of reducing scums. Furthermore, other benefits from adding surfactants including enhancing the adjust development efficiency and increasing production throughput.
With the home use flat screen displays becoming more common to life in recent years, the photo-resist for color filter of the liquid crystal display is added with additives such as dispersed dyes, pigments, cross-linking agents, photo initiators, or unsaturated multi functional monomers and etc for improving the color contrast and saturation, or the adhesive property of the photoresist film, or the mechanical toughness of color filter, or reducing the exposure dose for hgily throughput and saving energy. Development with the use of developers having single nonionic surfactant is not ideal, particularly with black matrix pattern obtained from black photoresist, where after developed it is more susceptible to scum in the unexposed region film, and may include residues of resins or pigments, and resulted in discoloration and other prohibited flaws.
As developing progresses, scum tends to accumulate and resulting dissolved dye microparticles or other water insoluble residues in the development tank to settle on top of the substrate or photoresist film, and causing scum, surface contaminants and others to remain on color filter.
The aforementioned alkaline developer is more susceptible to absorb carbon dioxide gas in the atmosphere, and the alkaline component is more easily reacted with the acidic functional group to cause the pH of the developer greatly change during the developing process and affect the stability of the developer. In Japanese Patent application Laid-open No. 5-88377 or Laid-open No. 10-213908 disclosed the use of general alkaline matter and its conjugated acid-base pair for allowing alkaline developer to have the pH buffer capability as well reducing the uncontrolled factors in the developing process.
However, the aforementioned materials or methods can not satisfy the stability and resolution of the developer.